KR102013983B1 - Method and server for authenticating an application integrity - Google Patents

Abstract

According to the invention, the integrity authentication server receives an authentication request for the application from the mobile terminal is installed, the authentication server generating the query information for the application in response to the authentication request, the query information Transmitting to the mobile terminal, receiving response information generated in response to the query information from the mobile terminal, wherein the response information is based on the query information and a unique value for the application by the mobile terminal. The application integrity authentication method and the integrity authentication server are provided, comprising the step of determining whether to convert the application based on the receiving step, and the unique value included in the response information.

Description

Application integrity authentication method and authentication server {METHOD AND SERVER FOR AUTHENTICATING AN APPLICATION INTEGRITY}

The present invention relates to a method and an authentication server for authenticating an application's integrity by checking whether an application is intentionally converted.

As smart phones, that is, mobile terminal functions, have been advanced, they have various functions such as DMB, word processors, MP3 players, video players, and cameras, not just telephone functions. Accordingly, the mobile terminal has exceeded the utilization rate of independent functional devices such as PCs, cameras and MP3 players, and this trend is expected to continue.

As mobile terminals increasingly play an important role in life, various personal information required by the user is stored. In addition, when a mobile terminal is lost or hacked, personal information of the user of the mobile terminal is stored externally. The risk of exposure to public health is increasing. In particular, in the case of functions related to banking and settlement, exposure of personal information does not end at the level of exposing personally identifiable information, but there is also concern that a person's financial property may be damaged. Therefore, in the case of applications related to banking and payment, security functions such as additional authentication are often strengthened than applications of other functions.

The mobile terminal is preloaded with an application to be used, or a user additionally downloads and uses the application. That is, the performance of the mobile terminal is based on the application of the application. Therefore, the security of the application is very important to secure the mobile terminal. Recently, some hackers who attempt to hack through applications often induce modifications of applications normally made by manufacturers to be downloaded to a mobile terminal of a general user. If the modified application is installed in the mobile terminal, there is a risk of hacking through the personal information desired by the hacker.

Specifically, after confirming the original source of the application through the reverse engineering method of the normally produced application, modify the original source to the content desired by the hacker, and then upload it to the App Store again, an unspecified number of users Increasingly, victims of downloads and installations are being exploited.

As a countermeasure to reduce such exploit damage, there is a need for a technology that can authenticate the integrity of an application.

As an example of the prior art, a central server stores hash values of various applications in advance, and checks in a central server when the mobile terminal obtains confirmation of the integrity of an application installed in the terminal. Here, the mobile terminal obtains a hash value of the installed application and sends the hash value to the central server. The central server checks the integrity of the application by comparing the received hash value with the previously stored hash value.

However, the hash value of the application can be obtained to a third party in various ways. For example, there is still a problem in that it is possible to obtain a hash value by identifying and bypassing logic that calculates a hash value statically through reverse engineering, and use the hash value as it is by intercepting communication with a server.

According to the present invention, when there is an application authentication request of a mobile terminal, whether the application is converted, that is, application integrity, can be confirmed through an authentication server dedicated to authentication.

In addition, when the application integrity is authenticated, the present invention may generate an OTP token to protect the integrity verification result again.

According to an embodiment of the present invention, an authentication server may include receiving an authentication request for the application from a mobile terminal in which an application is installed; Generating, by the authentication server, query information for the application in response to the authentication request; Transmitting the query information to the mobile terminal; Receiving response information generated in response to the query information from the mobile terminal, wherein the response information is generated by the mobile terminal based on the query information and a unique value for the application; And determining whether to convert the application based on the unique value included in the response information.

In addition, the application integrity authentication method, if it is determined that the application is not converted, generating a one time password (OTP) token; And transmitting the OTP token to the mobile terminal, wherein the OTP token may include time stamp information which is time information when the authentication server generates the OTP token.

In addition, the OTP token may further include a first encryption key shared with the service server. The OTP token may be validated using the current time and the time stamp of the service server.

The application integrity authentication method may further include determining whether to convert by comparing the unique value of the application pre-stored in the authentication server with the unique value included in the response information.

The determining may further include decrypting the response information with an encryption key, wherein the response information includes the first hash value generated by using the query information and the unique value as input values for a hash function. It may be a value encrypted with an encryption key.

The query value may include a random value generated through a random number function.

According to another embodiment of the present invention, a communication unit for receiving an authentication request for the application from the mobile terminal is installed; A storage unit for storing information about the application; And a controller for determining whether to convert the application according to the authentication request, wherein the controller generates query information for the application by using the stored information in response to the received authentication request, and generates the communication unit. Allow the query information to be sent to the mobile terminal, and when response information generated in response to the query information is received from the mobile terminal, based on a unique value for the application included in the response information. An application integrity authentication server for determining whether to convert can be provided.

In addition, when the controller of the application integrity authentication server determines that the application is not converted, generates a one time password (OTP) token, and controls the communication unit to send the OTP token to the mobile terminal, the OTP token The authentication server may include time stamp information which is time information at the time of generating the OTP token.

The OTP token may further include a first encryption key shared with a service server, and the OTP token may be validated using the current time and the time stamp of the service server.

The storage unit of the application integrity authentication server may pre-store the unique values for the application, and the controller may compare the unique values pre-stored in the storage unit with the unique values included in the response information to determine whether to convert. have.

The response information may be a value obtained by encrypting a first hash value generated by using the query information and the unique value as an input value to a hash function with an encryption key, and the controller may decrypt the response information with the encryption key. have.

According to another embodiment of the invention, the wireless communication unit for transmitting an integrity authentication request for the application to the integrity authentication server; And a control unit for controlling the wireless communication unit, wherein the control unit, when receiving the query information corresponding to the integrity authentication request through the wireless communication unit, checks a unique value for the application, and checks the unique value and the unique value. It is also possible to provide a mobile terminal, which controls to generate response information based on the query information and transmit it to the integrity authentication server.

The response information may be encrypted with an encryption key using a first hash value generated by using the query information and the unique value as input values for a hash function.

The control unit of the mobile terminal may transmit the OTP token to a service server associated with the application when receiving an One Time Password (OTP) token from the integrity authentication server as a result of the integrity authentication.

The application authentication server and the authentication method according to at least one embodiment of the present invention can confirm application authentication in a state where security is enhanced through a dedicated server dedicated to application authentication.

In addition, the present invention provides an effect that the service server associated with the mobile terminal can easily check the integrity authentication results of the application by providing the service server by generating an OTP token having the success authentication information at the time of integrity authentication, the integrity authentication server can do.

1 is a diagram illustrating an installation file structure of an application.
2 is a diagram showing a reverse engineering scheme;
3 illustrates an integrity authentication system in accordance with the present invention.
4 illustrates an integrity authentication server in accordance with the present invention.
5 illustrates a mobile terminal according to the present invention.
6 illustrates the overall flow for an integrity authentication scheme in accordance with one embodiment of the present invention.
7 is a diagram illustrating a flow of a query / response operation in an integrity authentication method according to an embodiment of the present invention.
8 is a diagram illustrating a flow of OTP generation / delivery among integrity authentication schemes according to an embodiment of the present invention.

Hereinafter, a mobile terminal according to the present invention will be described in more detail with reference to the accompanying drawings. The suffixes "module" and "unit" for components used in the following description are given or used in consideration of ease of specification, and do not have distinct meanings or roles from each other.

The mobile terminal described herein may include a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), navigation, and the like. However, it will be apparent to those skilled in the art that the configuration according to the embodiments described herein may also be applied to fixed terminals such as digital TVs, desktop computers, etc., except where applicable only to mobile terminals.

On the other hand, the term "integrity" as used herein means to maintain the accuracy and consistency of the data or application, and to ensure that there is no defect or mismatch in the data or application. In the present invention, by checking whether the application is converted, it is possible to finally determine whether the application integrity.

1 is a diagram illustrating an example of an installation file structure of an application.

The present specification is described based on the Android OS for convenience of description, but the present invention can be applied to other mobile OS, iOS, Windows Mobile (WM) and the like.

1 illustrates an Android package file (Apk) as an example of an installation file of an Android application. APK is a variant of the JAR format, in standard zip compression format.

AndroidManifest.xml file is located in the top level folder and contains the permission information required to run the application. It also includes operation setting information for the main component.

The Classes.dex file is a DEX file that contains all the code needed to run the application. File written in Java language is a file converted from compiled class file using DX tool.

The Res folder consists of files that define layouts, strings, and so on. The lib folder contains compiled native libraries, and the assets folder can contain additional files.

2 is a diagram illustrating the flow and repackaging of reverse engineering.

Reverse engineering is a discipline in software engineering that involves tracking back already created systems to obtain data such as initial documentation or design techniques.

Hereinafter, an example in which reverse engineering is applied to an application will be described.

First, unpacking the APK file 201 using apktool extracts the native library 205 and the smail code 206 as contents, and disassembles the DEX form as shown in FIG. 2. An additional smail directory is created with the files.

When unzip the APK file 201, the classes.dex file 202 can be obtained. The classes.dex file 202 is converted into classes_x.jar 203 which is a jar file format using the dex2jar program. Jar files can be converted to Java source files 204 using a JAVA compiler tool such as JD-GUI. Reverse engineering is primarily done in this form because it is easy to analyze externally in the form of Java source files.

The process of going to the modulated Apk 207 is called repackaging and is regenerated by the hacker's modulation app in this process. Decomposition was carried out in the above two ways, but in reverse order, recombination is achieved. If you use the first apktool, you have to modify the smail code directly. In this case, it is difficult to analyze the code directly. )

On the other hand, in the case of disassembling the java source code in the second manner, the java source code is modified in the reverse order, reversely compiled and assembled to create a class.dex file, and the remaining original is compressed to generate a modulated Apk 207.

On the other hand, the smail code 206 is generated by the disassembler and has the same structure as the Java source file 204, but there is a problem in readability. Therefore, this step is not often performed, but when the Java source file 204 is obfuscated so much that decompilation is impossible, the smail code 206 may be directly modified. Thereafter, the modified APK file 207 can be generated by modifying the file generated by using apktool and packaging the contents again by using apktool. You can also add app signatures using the jarsigner tool to make them installable.

Hereinafter, the hash value Hash will be described.

The hash value is obtained from the hash function. The hash function is a function that maps arbitrary data of arbitrary length to data of fixed length. In other words, a fixed length data calculated by applying a hash function is called a hash value. Hash values may be called hash codes, checksums, in other words. In the present invention, it can be interpreted as a unique value for an application that can authenticate the integrity of the application.

In order to prevent running a tampered APK, i.e. an application that has a flaw in its integrity, it is common to perform an app's integrity authentication using a hash value.

Here, the hash value is calculated for the APK file of the running application, and is securely transmitted to the server and then compared with the hash value of the original APK file stored in the server.

Hash values can be used commonly in the security field. If a hash value is obtained, it is impossible to restore the original data from the hash value. In other words, the hash function has the characteristics of a one-way function. Thus, there can be only one original data with the same hash value. Therefore, it can be used to authenticate data integrity, such as passwords.

In addition, integrity authentication may be performed using a signature used when registering an application together with a hash value. The signature contains information about the certificate information and may be included in the application in such a way as to leave a fingerprint on the application. Therefore, in the case of a tampered application, if the same certificate is not provided, a difference may occur between the original and the integrity authentication.

3 is a diagram illustrating an application integrity authentication system according to the present invention.

The application integrity authentication system 300 according to the present invention may be composed of an authentication server 301, a mobile terminal 302, and a service server 303. However, the integrity authentication system 300 is not necessarily limited thereto, and the function of the service server 303 and the authentication server 301 may be operated in one server.

The authentication server 301 authenticates the integrity of the application installed in the mobile terminal 302. When the application authentication request is received from the mobile terminal 302, the integrity of the application is determined according to certain logic, and the result is sent back to the mobile terminal 302.

The mobile terminal 302 mainly means a smartphone, but is not limited thereto, and refers to all terminals operating based on a mobile OS such as an Android OS and an Apple operating system (iOS). If the user wants to perform integrity authentication on an application installed in the mobile terminal 302, the mobile terminal 302 makes an integrity authentication request to the authentication server 301. When the integrity authentication result is received, the result is transmitted to the service server 303.

The service server 303 may be for one application, but may also perform functions for several applications. The service server 303 transmits and receives information necessary for the operation of the application when an application installed in the mobile terminal 302 needs to connect with an external network or when external authentication (personal authentication or application authentication) is required for application use. . In connection with the integrity authentication, when the mobile terminal 302 receives the integrity authentication result from the authentication server 301, the mobile terminal 302 transmits the integrity authentication result to the service server 303. The service server 303 sends the information or feedback corresponding to the result to the mobile terminal 302.

4 is a diagram illustrating an example of an integrity authentication server 301 according to the present invention.

The integrity authentication server 301 may include a storage unit 401, a communication unit 402, and a control unit 403.

The communication unit 402 may communicate with a plurality of mobile terminals 401, and may transmit and receive information therefrom. In addition, the communication unit 402 may be connected to an external network as needed. The communication unit 402 may occasionally receive external information required for integrity authentication through an external network. For example, the communication unit 402 may receive information about hash values and the like for a plurality of applications through an external network. The communication unit 402 may transmit a challenge value to the mobile terminal 401 and receive a response value thereto. In addition, the communication unit 402 may transmit the integrity authentication result information including the OTP value to be described later to the mobile terminal 401. In some cases, the communication unit 402 may directly transmit the integrity authentication result information including the OTP value to the service server 403.

The storage unit 401 may store various information necessary for authenticating the application. For example, profile information of an application may be stored. It can also store hash values for each application. The integrity authentication server 301 may be only for authentication of one application, but may also be a server for authenticating the integrity of multiple applications. Accordingly, app hash values of a plurality of applications may be stored in the storage unit 401. The storage unit 401 may be connected to the communication unit 402 and the control unit 403 to update profile information of the applications at a predetermined time period.

The controller 403 controls the overall operation of the integrity authentication server 301. In detail, the controller 403 may control operations of the storage unit 401 and the communication unit 403. In addition, the controller 403 may perform integrity authentication based on various information received from the mobile terminal 302. In detail, the controller 403 may perform integrity authentication using signals related to integrity verification included in the response value received from the mobile terminal 302, and generate a success / failure signal according to the result. In addition, the controller 403 may generate an OTP value upon successful integrity authentication.

Meanwhile, the integrity authentication server 301 has been described, but the service server 303 may also include a storage unit, a communication unit, and a control unit. As another example of the present invention, the service server and the integrity authentication server may be implemented as one server.

By software implementation, embodiments such as the procedures and functions described herein may be implemented in separate software modules. Each of the software modules may perform one or more functions and operations described herein. Software code may be implemented in software applications written in a suitable programming language. The software code may be stored in a storage unit and executed by a controller.

5 is a block diagram of a mobile terminal according to one embodiment of the present invention.

The mobile terminal 302 may include a wireless communication unit 501, a control unit 502, a memory 503, a user input unit 504, and an output unit 505. The components shown in FIG. 5 are not essential, so that a mobile terminal having more or fewer components may be implemented.

The wireless communication unit 501 may include one or more modules that enable wireless communication between the mobile terminal 302 and the external network or between the mobile terminal 302 and the network in which the mobile terminal 302 is located. For example, the wireless communication unit may include a broadcast receiving module, a mobile communication module, a wireless internet module, a short range communication module, and a location information module. The wireless communication unit 501 may download an application from an external app store. In addition, the wireless communication unit 501 may transmit and receive various information with the integrity authentication server 301. The wireless communication unit 501 may transmit and receive various information with the service server 303 for authentication or application driving.

The controller 502 typically controls the overall operation of the mobile terminal. For example, perform related control and processing for voice calls, data communications, video calls, and the like. In addition, a response value may be generated using various pieces of information in response to a challenge value received from the integrity authentication server 301.

The memory 503 may store a program for processing and controlling the control unit 502, and temporarily stores the input / output data (for example, a phone book, a message, an audio, a still image, a video, etc.). It can also perform a function. The memory unit 503 may also store a frequency of use of each of the data (eg, a phone number, a message, and a frequency of use of each multimedia). In addition, the memory unit 503 may store data regarding vibration and sound of various patterns output when a touch input on the touch screen is performed. The memory can be a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (e.g. SD or XD memory), RAM (Random Access) Memory, RAM), Static Random Access Memory (SRAM), Read-Only Memory (ROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Programmable Read-Only Memory (PROM), Magnetic Memory, Magnetic Disk, Optical Disk It may include at least one type of storage medium.

The user input unit 504 generates input data for the user to control the operation of the terminal. The user input unit may include a key pad, a dome switch, a touch pad (constant voltage / capacitance), a jog wheel, a jog switch, and the like.

The output unit 505 is used to generate an output related to sight, hearing, or tactile sense, and may include a display unit, a sound output module, an alarm unit, and a haptic module. The display unit 505 may display information processed by the mobile terminal 302. For example, the output unit 505 may output an error message in various ways when it is determined that the application is tampered with due to the integrity authentication failure.

The various embodiments described herein can be implemented in a recording medium readable by a computer or similar device using, for example, software, hardware or a combination thereof.

According to a hardware implementation, embodiments described herein include application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), and the like. It may be implemented using at least one of processors, controllers, micro-controllers, microprocessors, and electrical units for performing other functions. The described embodiments can be implemented by the controller itself.

By software implementation, embodiments such as the procedures and functions described herein may be implemented in separate software modules. Each of the software modules may perform one or more functions and operations described herein. Software code may be implemented in software applications written in a suitable programming language. The software code may be stored in a memory and executed by a controller.

6 is a diagram showing the overall flow for the integrity authentication method according to an embodiment of the present invention.

The integrity authentication server 301 first receives application profile information from the service server 303 (S601). The application profile information may include an application hash value (hereinafter, app hash value), package information, application version, app signing key, terminal USIM, and application name. The integrity authentication server 301 stores profile information received from the service server 303. In particular, the integrity authentication server 301 stores the app hash value for the application (S602).

When the mobile terminal 302 runs an application, the mobile terminal 302 transmits an integrity authentication request for the running application to the integrity authentication server 301 (S603). When the integrity authentication server 301 receives the integrity authentication request, the integrity authentication server 301 generates a challenge value for the application (S604). The integrity authentication server 301 sends the query value to the mobile terminal 302.

When the mobile terminal 302 receives the query value, the mobile terminal 302 generates a response value for the query value (S606). When generating the response value, the mobile terminal 302 generates using the app hash value of the application. The mobile terminal 302 sends the response value back to the integrity authentication server 301.

The integrity authentication server 301 verifies the integrity of the application by analyzing the response value (S608). The integrity authentication server 301 generates an integrity authentication result after integrity verification (S609). The integrity authentication server 301 transmits the integrity authentication result to the mobile terminal 302. The mobile terminal 302 operates according to the authentication result (S611). For example, the mobile terminal 302 may generate an error message if authentication fails. The mobile terminal 302 transmits the authentication result to the service server 303 (S612). In the present invention, when generating an authentication result, it may include an OTP value. The mobile terminal 302 may transfer the authentication result from the integrity authentication server 301 to the service server 303 immediately after receiving the authentication result. Alternatively, the mobile terminal 302 may send an authentication result to the service server 303 when the mobile terminal 302 needs to connect to the service server 303 through an application.

Hereinafter, the flow of the query / response part of the integrity authentication method of the present invention.

Referring to Figure 7, the flow of the query / response operation of the integrity authentication scheme is shown.

Query / response authentication is a widely used method in cryptography and can be implemented in a variety of ways, depending on its implementation.

Depending on the method of encrypting the content of the query / response, various methods such as hash function, symmetric key, asymmetric key, and digital signature can be selected or combined.

Meanwhile, the server may have one-way and two-way authentication according to a method for participating in authentication between terminals. An example of a unidirectional example is when the integrity authentication server 301 only performs authentication on the mobile terminal 302, and the mobile terminal 302 further strengthens the validity of the integrity authentication server 301 in both directions. This can be an example of authentication. In the case of two-way authentication, a random value may be generated in the mobile terminal 302 by using a shared secret key to exchange a message with the server 301.

The query / response operation described in FIG. 7 will be described in more detail with reference to steps S603 to S610 related to the query / response generation described in FIG. 6.

The mobile terminal 302 drives an application (S701). The application is an application installed in the mobile terminal 302. The present invention may operate every time the application is run, but preferably, may be operated when the application is first installed after the application is installed. The mobile terminal 302 transmits an integrity authentication request for the application through the wireless communication unit 501 (S702).

When the integrity authentication server 301 receives the integrity authentication request, the integrity authentication server 301 generates a random number using a random number function (S703). Random numbers generated through random functions can also be called nonce. Here, the random value is a value that is used once, and a different value may be generated each time it is generated. The integrity authentication server 301 is generated with profile information (app hash value, terminal USIM, application name, package information, company name, application version, app signing key) and random number function for the application pre-registered in the server 301. The hash function is driven by using a random value as an input value. The integrity authentication server 301 generates a query value through a hash function (S704). In the present invention, preferably, the integrity authentication server 301 may generate a query value by using an arbitrary value, package information, an application version, a pre-shared key, and the like as an input value of a hash function. The generated query value is transmitted to the mobile terminal 302 (S705).

When the mobile terminal 302 receives the query value, it calculates an app hash value for the application (S706). Optionally, the mobile terminal 302 may also load the stored app hash value. Challenge-Response authentication uses random values (one-time use numbers) as questions and uses the value to be authenticated (app hash value) as a response to prevent replay attacks. It is meaningful to have. On the other hand, since the response value may be exposed to plain text by session hacking on the network, it is generally not possible to analyze the value by using a hash function or by using encryption.

More specifically, the mobile terminal 302 generates the intermediate hash value by using the calculated app hash value and the query value as inputs to the hash function. This may further prevent third parties from stealing the app hash value.

The mobile terminal 302 encrypts the intermediate hash value with the app signing key (S707). Here, the app hash value is an encryption key specific to the application and may represent the application. The app signing key can be used to sign an application with the developer's own signing key before the application is finally uploaded to the App Store. The app signing key can be used to verify that the application you developed is authentic when the application is distributed through the app store. The app signing key may be stored together with the integrity authentication server 301 when transmitting the application profile information as described above. The mobile terminal 302 generates a response value based on the encrypted value (S708). When encrypting, use the symmetric key method. Accordingly, the mobile terminal 302 and the integrity authentication server 301 may use the same app signing key as an encryption key for encryption / decryption. However, you can optionally use asymmetric keys. Thus, mobile terminal 302 uses an app signing key, while integrity authentication server 301 may use a different encryption key and vice versa.

When using an asymmetric key, the processing speed is relatively slower than that of a symmetric key, but there is an advantage in that key management is easy. Mainly implemented using RSA algorithm, it creates a pair of public key and private key and exposes public key.

When applied to the present invention, the mobile terminal 302 can be encrypted by using the public key disclosed by the server, and the server 301 can decrypt the response value by using the secret key.

Meanwhile, a hybrid scheme is also used. First, the mobile terminal 302 and the integrity authentication server 301 share a secret key to be used for the symmetric key cipher using an asymmetric key cipher technique. That is, the mobile terminal 302 arbitrarily generates a "symmetric key cryptographic secret key" (key to be used for the symmetric key cryptography) and encrypts it with the public key disclosed by the integrity authentication server 301, and transmits it to the integrity authentication server 301 itself. The secret key is decrypted to obtain the "symmetric key secret", and then used as the secret key in the symmetric key cipher during the query / response process.

However, this approach can be problematic if the processing speed is sensitive. This can be lengthy when running an application, which may not be acceptable to service customers. However, if security is more important, it can be considered.

In addition, when encrypting, the app signing key can be stored using a white box encryption method. The white box encryption method is a method of mixing an encryption key with an encryption algorithm implemented in software in order to make it impossible to infer the encryption key of the encryption algorithm. Therefore, even if an attacker analyzes the internal operation of the algorithm, an encryption key such as an app signature key may not be easily inferred.

Meanwhile, the response value may be generated by encrypting the app hash value with an app signing key instead of using the hash function.

The mobile terminal 302 transmits the generated response value to the integrity authentication server 301 (S709).

The integrity authentication server 301 decrypts the response value (S710). Here, the integrity authentication server 301 decrypts the response value using the stored app signing key. As a result of the decryption, the integrity authentication server 301 may obtain an intermediate hash value. Since the integrity authentication server 301 already knows the random value information transmitted by the integrity authentication server 301, the integrity authentication server 301 knows the intermediate hash value and the random value. Here, it is difficult to directly check the input value through the intermediate hash value. However, since the random value that is an input value and the intermediate hash value that is a result value are known, and the hash function is already known, the control unit 403 of the integrity authentication server 301 can infer the app hash value. That is, if the number of cases is confirmed, the controller 403 may check the app hash value transmitted by the mobile terminal 302 through an arbitrary value and an intermediate hash value.

The integrity authentication server 301, that is, the controller 403 compares the app hash value (S711). The storage unit 401 of the integrity authentication server 301 stores an app hash value for the application. Here, the control unit 403 can check the integrity of the application by comparing the app hash value identified from the response value and the app hash value stored in the storage unit 401. If the app hash value is the same, it can be determined that there is no conversion of the application. On the contrary, if the app hash values are not the same, it may be determined that there is a conversion of the application, and it may be assumed that there is a conversion by the attacker.

Integrity authentication is determined by comparing the app hash values (S712). If the integrity is authenticated, the controller 403 generates an OTP token as an indication of success (S713). A result value is generated using the integrity authentication result (S714), and the result value is transmitted to the mobile terminal 302.

8 is a diagram illustrating a flow of OTP generation / delivery among integrity authentication schemes according to an embodiment of the present invention.

In S713 of FIG. 7, an OTP token is generated as a result of integrity authentication. Here, the token method uses time synchronization. In the time synchronization method, when calculating the MAC response value (using a hash function), the current time is additionally input to the pre-shared key. In other words, it is possible to synchronize based on the fact that mutually different subjects (for example, a server and a user) have a common time. Here, the one-time token cannot modify the time, but can cause the password to change once every certain time (eg 1 minute). In this case, since the server may have an error in time with the user, it may be recognized as a valid token if it is identified as a time within a certain range to correct this.

Hereinafter, the OTP generation / delivery method of the integrity authentication method will be described with reference to FIG. 8.

The integrity authentication server 301 generates a secret key (S801) and the service server 303 stores the secret key (S802). In this case, the secret key may play a role in which the integrity authentication server 301 and the service server 303 identify each other.

The integrity authentication server 301 may transmit not only an OTP token but also application specific information and terminal unique information (USIM, ESIM) to the integrity authentication result value in S715 of FIG. 7.

The OTP token value is a combination of the service server, time stamp (current time), and secret key (PreShared Key) value, which may be a hash value generated through a hash function. In addition, the app signature key or success information (O X) may be included as an input. There are various ways to generate an OTP token value, and using a hash function may be one of them. For example, it may be generated by encrypting an OTP token value with a specific encryption key. Importantly, the OTP token value must contain information about the time stamp when the OTP token was created.

The mobile terminal 302 checks the integrity authentication result (S803), and transmits the integrity authentication result to the service server 303 (S802). Here, the mobile terminal 302 does not perform authentication on the corresponding OTP token value, and transfers the integrity authentication result to the service server 303 as it is. Preferably, the mobile terminal 302 is transmitted to the service server 303 immediately after, or within a predetermined time after receiving the result value from the integrity authentication server 301, but is not necessarily limited thereto. The OTP token value is generated only when the integrity verification succeeds and is used when the mobile terminal 302 connects to the service server 303.

The service server 303 performs an authentication operation on the OTP token (S805). If the OTP token value is a hash value using a hash function, the service server 303 may check whether the OTP token value matches the time stamp included in the OTP token value using information of the current time of the service server. The authentication operation on the OTP token can be performed by checking whether the value of the secret key and the current time information of the service server corresponds to the OTP token value. Compare the current time with the time stamp included in the token. If it is determined to be within a certain time range, it is judged as normal and authenticates the OTP token. However, if it is found out of a certain time range, the OTP token is denied authentication. If the authentication is denied, the service server 303 determines that the mobile terminal 302 or the application is invalid and may retry three times, but is not limited to the number of times.

If the OTP token is authenticated, the user of the mobile terminal 302 may be authenticated (S806). If the user is authenticated, allow application login to the service server 303. In addition, the mobile terminal 302 responds to the success (S807). The mobile terminal 302 operates according to success or failure (S808). In the case of success, the application is normally run, but in case of failure, the mobile terminal 302 may generate and display an error message.

On the other hand, optionally, the service server 303 may store data about success and failure. This can also provide app developers with data on success and failure visually.

In the present invention, as described above, the integrity authentication server and the service server can more clearly check the integrity result through the OTP token value generated only when the integrity authentication is successful.

301 Integrity Authentication Server
302 mobile terminal
303 service server

Claims (17)

In the application integrity authentication method,
An authentication server receiving an authentication request for the application from a mobile terminal in which the application is installed;
Generating, by the authentication server, query information for the application in response to the authentication request, wherein the query information is information generated by inputting application profile information and an arbitrary value for the pre-registered application into a hash function. Generating step;
Transmitting the query information to the mobile terminal;
Receiving response information generated in response to the query information from the mobile terminal, wherein the response information is generated by the mobile terminal through a hash function based on an app hash value which is a unique value for the query information and the application. Receiving the encrypted intermediate hash value;
Decoding the response information to generate the intermediate hash value;
Identifying an app hash value for an application installed in the mobile terminal based on the intermediate hash value and the query information, wherein the query information, the first input value, and the second input are first input values to a hash function; Identifying the second input value for the hash function using the intermediate hash value that is a result of the hash function for the value, and identifying the inferred second input value as the app hash value;
Determining whether to convert an application by comparing the identified app hash value with an app hash value stored in the authentication server; And
If it is determined that the application of the mobile terminal is not converted, the authentication server sends a one time password (OTP) to the mobile terminal, the mobile terminal accesses the application service of the service server using the OTP token Characterized in that, the transmitting step,
Application integrity authentication method. The method of claim 1,
The step of transmitting the OTP token,
Generating an One Time Password (OTP) token if the authentication server determines that the application has not been converted;
The OTP token includes time stamp information that is time information when the authentication server generates the OTP token,
The OTP token further comprises a first encryption key shared with the service server,
Application Integrity Authentication Method .. The method of claim 2,
Prior to receiving the authentication request,
The authentication server further receiving the application profile information from the service server,
The application profile information includes at least one of the app hash value, package information, an application version, an app signature key, the mobile terminal information, and an application name.
Application integrity authentication method. The method of claim 1,
The service server allows an application service access to a service server of the mobile terminal only when the service server receives the OTP token from the mobile terminal and is authenticated.
Application integrity authentication method. The method of claim 1,
In the step of transmitting the OTP token,
Wherein the authentication server transmits at least one of the application specific information and the mobile terminal specific information together with the OTP token.
Application integrity authentication method. delete delete An application integrity authentication server,
A communication unit receiving an authentication request for the application from a mobile terminal in which the application is installed;
A storage unit for storing information about the application; And
And a controller for determining whether to convert the application according to the authentication request.
The control unit,
Generate query information for the application by using the stored information in response to the received authentication request,
Cause the communication unit to transmit the query information to the mobile terminal;
When the response information generated in response to the query information is received from the mobile terminal, the response information is decoded to generate an intermediate hash value, and to the application installed in the mobile terminal based on the intermediate hash value and the query information. Checks the app hash value for
The application hash value stored in the authentication server is compared with the checked app hash value to determine whether to convert the application,
If it is determined that the application is not converted, characterized in that for controlling the communication unit to transmit an One Time Password (OTP) to the mobile terminal,
The query information is information generated through a hash function using application profile information and an arbitrary value of the pre-registered application as input values,
The response information is a value obtained by encrypting an intermediate hash value generated by the mobile terminal through a hash function based on the query information and an app hash value that is a unique value for the application.
In the checking of the app hash value, the second input is performed using the query information, which is a first input to the hash function, and the intermediate hash value, which is a result of a hash function of the first and second inputs. Inferring, confirming the inferred second input as the app hash value,
When the mobile terminal receives the OTP token, the mobile terminal uses the OTP token to access the application service of the service server,
Application Integrity Authentication Server. The method of claim 8,
The control unit,
If it is determined that the application has not been converted,
Generating an One Time Password (OTP) token, controlling the communication unit to transmit the OTP token to the mobile terminal,
The OTP token includes time stamp information which is time information when the application integrity authentication server generates the OTP token,
The OTP token further comprises a first encryption key shared with the service server,
Application Integrity Authentication Server. The method of claim 9,
The communication unit receives the application profile information from the service server before receiving the authentication request from the mobile terminal,
The application profile information includes at least one of the app hash value, package information, an application version, an app signature key, the mobile terminal information, and an application name.
Application Integrity Authentication Server. The method of claim 8,
The service server allows an application service access to the service server of the mobile terminal only when it is authenticated by receiving the OTP token from the mobile terminal.
Application Integrity Authentication Server. The method of claim 8,
The control unit,
When the OTP token is transmitted from the mobile terminal, at least one of the application specific information and the mobile terminal unique information is transmitted together with the OTP token.
Application Integrity Authentication Server. delete delete A wireless communication unit which transmits an integrity authentication request for an application to an integrity authentication server; And
A control unit for controlling the wireless communication unit,
The control unit,
When the query information corresponding to the integrity authentication request is received through the wireless communication unit, the unique value for the application is checked, and response information is generated based on the unique value and the query information and transmitted to the integrity authentication server. Control it,
When receiving an One Time Password (OTP) token from the integrity authentication server as a result of integrity authentication, the OTP token is controlled to be transmitted to a service server associated with the application.
The service server allows the mobile terminal to access the application service only when the OTP token is normally authenticated.
Mobile terminal. delete delete

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